Spool valves are known for disrupting fluid flows within passages, including routing a flow of fluid from an inlet passage to one or more outlet passages. Specifically in internal combustion engines, spool valves are often used to route a fluid, such as engine coolant, from an inlet to one or more outlets.
Typical spool valves are prone to hysterisis and may require relatively large actuator forces to move a spool member within a housing. These negative attributes are often attributed to pressure imbalances that may be present within a valve during operation. Often, a net pressure difference between an open and a closed passage may impart a net force onto surfaces of the spool, necessitating an actuator to overcome this net force in moving the spool from one position to another.